Chemistry: Cations + Anions

Question 1

Using the flame test: The result was a brick-red flame. So what was the cation?

Answer 1

Calcium

Question 2

Using the NaOH test: The result was a blue precipitate. What was the cation?

Answer 2

Copper

Question 3

What test should you use and what result should you get to find Potassium?

Answer 3

Flame test: Lilac flame

Question 4

What element makes a sludgy green precipitate and what test must have been used?

Answer 4

NaOH test: Iron (II)

Question 5

What tests can you use to find a Cation?

Answer 5

Flame test, NaOH or damp red litmus paper because ammonia is a Cation.

Question 6

If the flame test for a cation was used, what colour would sodium make the flame change to?

Answer 6

Yellow-orange

Question 7

What colour does lithium go in the flame test?

Answer 7

Crimson-red

Question 8

If the NaOH test is used, what colour would an Iron (III) precipitate go?

Answer 8

Brown

Question 9

What tests are there for anions?

What are they used to show?

Answer 9

Add nitric acid then silver nitrate- Halides
add HCl then barium chloride- Sulfates
add HCl- Carbonates (You also need to add lime water to see if CO2 is produced)

Question 10

What colour is a chloride precipitate from a silver nitrate test?

Answer 10

White

Question 11

Silver nitrate test- result went cream… what was the anion?

Answer 11

Bromide

Question 12

Silver nitrate test - result was yellow… what was the anion?

Answer 12

Iodide

Question 13

What colour must a sulfate ion go if you add HCl then barium chloride to the compound?

Answer 13

White

Question 14

How do you know if you have a carbonate

Answer 14

Add HCl, if CO2 is produced, the you have a carbonate. You can test for the CO2 using lime water.